Customer-satisfaction surveys -- increasingly used by businesses to determine rewards for employees -- suffer from systematic prejudices, new research suggests.

Although many businesses think they are rewarding the best employees by relying on what customers say, that system effectively discriminates against women and minorities and can undermine business performance, according to a study to be published in the Academy of Management Journal.

"Right now, businesses think customer satisfaction surveys are highly reliable," said lead author David R. Hekman, assistant professor of management at the University of Wisconsin at Milwaukee. "They are highly reliable -- but they are reliably wrong."

Hekman and his colleagues evaluated 12,091 patient reports about 113 doctors working at a large HMO in the Pacific Northwest. They also studied objective data about the doctors. The regularity with which doctors place heart patients on certain drugs, for example, is a good measure of the quality of their care. The number of e-mails doctors send patients is a measure of their accessibility. And the number of questions doctors ask patients during checkups is a measure of their diligence.

In all these domains, however, Hekman found that these objective measures of performance correlated with patient satisfaction reports only when the doctors were white men. For women and minorities, extra quality, accessibility and diligence not only did not result in better evaluations by patients -- they produced worse evaluations.

"E-mails make patients happier only if you are a white male doctor," Hekman said, noting that 6 percent of the doctors' income was based on the patient ratings. "It does not make sense -- working harder seems to be counterproductive for women and minorities."

In a related experiment involving bookshop employees, volunteers were shown two videotaped interactions between a customer and a sales clerk and were told to imagine they were customers and rate the shop's service. Some were shown a white male sales clerk, while others were shown a black male clerk or a white female clerk. All the clerks were actors -- and everything else in the videos was identical, down to the script.

Those shown the white male clerk rated the service provided 19 percent higher than volunteers shown the woman or the black man. They also rated stores with white male clerks as being cleaner.

Hekman also studied the satisfaction levels of 3,600 golfers at 66 clubs nationwide. Clubs that employed higher numbers of Latinos were rated more poorly than clubs employing fewer minorities -- even when they performed identically on objective measures.

Hekman said the point was not to suggest that because white men generate higher customer satisfaction, companies act "rationally" when they give larger bonuses to white men than to women and minorities, but to alert customers about potential biases and businesses about the limitations of customer-satisfaction reports.

-- Shankar Vedantam

Move Over, Mickey

Do you remember Mr. Ed -- the talking horse on the popular 1960s television show? Well, no one has found a horse or any other animal yet that can talk. But scientists in Germany may have taken a small step toward the Dr. Doolittle world of talking animals.